Control mechanism



March 15, 1932. P. DE LNGIE ET AL 1,849,481

CONTROL .IECHMISM Filed May l. 1926 2 Sheets-Sheet l March l5, 1932.A P.DE LANGIE ET AL 1,849,481

CONTROL MECHANISM Filed May l. 1926 2 Sheets-Sheet 2 %,g..

lum AV Patented Mar. 15, 1932 UNITED STATES PATENT OFFICE PETER DELANGIE AND eoDrnnY A. DE LANGIE, or NEWPORT, RHODE ISLAND CONTROLMEcrtANIsm:

Application filed May 1, 1926. Serial No. 106,035.

This invention relates to an improved control mechanism for electricallyheated devices and more particularly devices of the character whereinthe electric circuit is automatically broken when the temperaturereaches a predetermined point.

One object of the present invention is to provide a device of thischaracter which is capable of operating automatically to break vtheelectric circuit when the temperature reaches such a point as to renderfurther heating inadvisable, as well as manual means forv breaking thecircuit when desired.

Another object of the invention is to provide a quick action means formaking or breaking the circuit to prevent arcing of the current acrossthe terminals.

A further object of the invention is to provide a quick action means formaking or breaking the circuit and a heat `responsive means adapted tooperate the said means whereby the circuit breaking means will beoperated to prevent excessive heating.

Other objects and advantages of the invention relate to certain improveddetails of construction and methods of operation as will be more fullyset forth'inthe following detailed description to which reference ismade for a more specific exposition of the advantages of the invention.

Referring to the drawings:

Fig. l is a side elevational View of a conventional form of sad-iron, aportion of which is brokrn away to show the position of a. thermostaticmember located adjacent to the heating element, and illustrating theposition of our improved structure relative to said iron.

Fig. 2 is a top plan view of the operating parts of the controlmechanism, the parts being shown in position for breaking the electriccircuit.

Fig. 3 is a view similar to Fig. 2 with the parts shown in the positionwhich they occupy when the electric circuit is closed.

Fig. 4 is a vertical sectional View of the control mechanism, takenalong the line 4 4 of Fig. 2.

Fig. 5 is a vertical sectional view showvcurling devices, andelectrically heated devices generally.

The improved structure which we have described herein may beincorporated in the electrically heated device as forming an integralpart thereof, or may be provided in the form of an attachment capable ofready application to certain conventional forms of electrically heatedVdevices now in common use. As illustrated in F ig. l of the drawingsthe structure is shown as an attachment capable of application to aconventional type of sad-iron with only minor changes therein, such as,the arrangements of the electric circuits, etc.

Referring to the' drawings; the sad-iron is designated by the numeral l,and is pro'- vided with the usual outer casing 2 Within which is locatedthe base 3 and a conventional heating coil' (not shown) to which isconnected the Wires 4: and 5 for making an electric circuit through thecoil. The cord plug 6 is of the usual construction, and is connected tothe terminals 7 in the usual manner.

A separate housing 8 is secured to the rear of the iron l by means ofscrews or other suitable fastening devices 9 and a layer of asbestos orother -suitabl'eJ heat insulating material 10 may be interposed betweenthe iron l and the housing 8 to prevent excessive heat being transmittedto the mechanism in the housing.

A hollow tube 11 provided with closed ends and containing a small amountof expansible fluid capable of expanding and contracting Withincrease ordecrease of temperature, is positioned within the housing and providedwith an end port-ion 12 which extends from the housing 8 into the casing2 and is positioned therein/adjacent the heating element or coiland base3 of the iron where it will be quickly affected by changes of tempera-yture in the heating coil. rIhe end portion of 5 the hollow tube whichextends within the iron is substantially circular in cross section butthe opposite end'thereof is preferably flattened to give the samel anoval cross section from about the point indicated by the numeral 15. yThe closed hollow tube 11 is firmly secured a supporting block -16 whichis in turn /attached to the housing by screws or similar fasteningdevices 17, thus firmly .an- 15 choring the hollow tube so that the end18 of the tube will be free to move uninfluenced by the position of theend 12 thereof. The end `18 of the closed tube is curved as shown inFigs. 2 and 3, andas the ends .thereof 20 are closed the curved end 18move into the position in Fig. 2 as the iiuid in the tube expands underthe influence of increased temperature or move into the position shownin Fig. 3 as the fluid in the tube contracts by reason of a decrease intemperature.- In this way the curvedend 18 of the tube will move intoengagement with the switch mechanism 20 or out of engagement therewithas the heat of the iron increases or diminishes. The extent of movementof the curved end 18 of the tube and its responsivenessto greater orless variations in temperature may be varied and controlled by varyingthe size of the parts and the quantity and'character of the expansiblefluid. 7 l

The switch' mechanism designated generally by the numeral 20, comprisesa base 21, internally recessed as at 22, and which may be formed offibre, vulcanite or other insulat- `ing material, the base being securedto the vertical wall 24 of the housing by rivets 25, 26 or any othersuitable and desired fastening means. A switch plate 28 is firmlysecured at one end to the base 21 by the rivets 25 and extends forwardlyover the recess 22 and a bearing 30 formed upon the base, the forwardend portion of said plate carrying a lcontact/member 32 which isentirely insulated therefrom by insulating ma- 59 teral 33. The switchplate 28 is provided intermediate its ends and directly above the recess22 with a rounded depression or concavo-convex portion- 35, the convexside of which normally extends upwardly or on the 'be seen that thespring switch plate 28 is opposite side of the switch from the base 21.A thin flexible metal plate 36 is positioned above the switch plate 28and is provided upon the face adjacent to the switch plate with `abutton37 which is located directly opposite to the concavo-convexportion 35 of the switch plate and is normally-in contacttherewith. Apair of contact plates '39 and 40 are secured to the base 21 by therivets 26, these contacts being spaced from each other and-having aportion 410i the base located 'therebetween to prevent the contacts frommoving relative to each other. The contact 40 has the wire 4 connectedthereto, and the wire 42 is connected with the contact 39 and one of thecontacts 7 of the iron. In this way one of the contacts 7 of the iron isconnected directly with the heating coil and the other. contact 7 isconnected through the contact plates 39 and 40 and the contact point 32when the parts are in the position shown in Fig. 3. The switch plate 28is made of thin spring metal and the concavo-convex portion 35 isadapted to reverse itself by a quick movement in response to pressureupon the convex face thereof whereby it assumes the position shown inFig. 2, and the contact point 32 is lifted by a quick movement to breakthe circuit through the contact plates 39 and 40. When the pressure uponthe convex face of the concavo-convex portion 35 of the switch plate isreleased the switch plate immediately snaps back into the position shownin Fig. 3 thus closing the circuit by a quick movement of the contactpoint 32. The quick movement of thecontact member 32 in opening andclosing the circuits prevents arcing during theopening and closing ofthe switch. portion thereof cut away to form a central recess 22 as ismost clearly shown in Figs. 5 and 6, and the sides 45 of the base areeach cut away slightly to provide a slight forwardly extending incline46 which terminates just short of the bearing 30. By this constructionthe concavo-convex portion of the switch plate 28 is located over therecess 22 so that the recess 22 and the cut away portions of the sides45 permit the switch plate 28 to bend downwardly slightly as theconcavo-conve'x portion thereof is reversed by pressure exerted thereon,and the bearing 3() serves as a fulcrum for the switch plate in raisingthe contact member 32. The positions of the switch plate 28, met-alplate 36 and contact member 32 when the contact is in position to closethe circuit are shown in full lines in Fig. 6, and the positions ofthese parts when the circuit is open are shown in dotted lines on thatfigure. As illustrated herein, a block 50 is positioned above the plates28 and 36, and the screws 25 pass throughvthe plates and block and arethreaded into a plate 51 to hold the parts securely in position. Fromthe above it will provided with a pressure responsive portion and isinherently movable or capable ofdistortion upon the exertion of pressureon the pressure responsive portion to move' the con# tact 32 quickly outofengagement with the contact plates 39 and 40.

' A disk 53 is rotatably-supported by a pivot screw 54 on the' base 55ofthe housing 8 and carries a vertical arm 56 which'normally extendsupwardly throu'ghthe cover 57 `of the The base21 has the central housingwhere it may be grasped by the operator for rotating the disk 53. Thedisk 53 is also provided with pin 59 secured to the base 55 of thehousing projects within the slot 58 to limit rotation of the disk 53 ineither of two directions. A

coiled spring 60 is secured at one end to the disk 53 as at 62 and theopposite end of said spring is attached to a stud 63 carried by the base55, the spring being so arranged that it is located upon opposite sidesof the pivot 54 when the disk is rotated to its limit, as determined bythe pin and slot connection, in op- `posite directions.

The coiled spring 60 thus tends to retain the disk 53 in either of itsextreme positions of movement, and prevent its movement from either ofsuch positions until the disk is rotated manually through actuation bymeans of the arm 56. The disk 53 carries a pin 65 projecting upwardlytherefrom a suiiicient distance to enga-ge the curved end 18 of thehollow tube 11. A second coiled spring 66 has one end thereof attachedto the curved end of the closed hollow tube as at 67 while the oppositeend thereof is secured to the block 16 by an anchoring screw or similarmeans 68. The coiled spring 66 serves to supplement the tendency of thecurved end 18 of the closed hollow tube to return to the positionshownin Fig- 3 when the temperature of the iron falls below a predeterminedpoint. The base 55 of the housing is provided with hinge members 70cooperating with similar hinge members 71 carried by the cover 57 and apintle 72 to pivotally secure the cover to the base in such a mannerthat it may be raised when desired to give access to the mechanismenclosed in the housing. The front edge of the `cover is adapted toengage beneath a suitable clip 7 4 to retain the cover in closedposition, or if desired, the cover may be provided` with suitable screwsor other means for relea'sably vsecuring the same to the housing andthereby vrender the interior of the housing less readily accessible bythe usual operative while per- `mitting the same to be opened for thepurpose :of making repairs.

The extreme end of the closed hollow tube 1l is beveled as at 75 toenable the pin 65 to slide readily thereover when the disk '53 ismanually operated to break the circuit.

The curved end portion 18 of the closed hollow tube 11 which is free tomove in respouse to variations in temperature possesses a certain amountof resiliency, and the resilient character of the curved end 18 issupplemented vin its tendency to return to its normal position by thecoiled spring 66. The resiliency of the temperature responsive portionof the closed tube acts in conjunction with the resilient character ofthe switch :member or plate 28 to insure a quick and automatic return ofthe switch plate into position to close the circuit after actuation ofthe an arcuate slot 58, and aswitch plate by the movable portion of theclosed tube to break the circuit.

In the operation of one improved control mechanism the curved end 18 ofthe closed hollow tube moves outwardly from the position shown in Fig. 3to the position shown in Fig. 2 as the temperature of the iron andheating coil rises, and when the heat of the iron reaches apredetermined point the curved end 18 engages the plate 36 and forcesthe button 37 against the convex face ofthe concavoconvex portion 35 ofthe plate 28 with suflicient force to cause the concavo-convex portionto move into the dotted line position shown in Fig. 6 whereby thecontact point 32 is raised by a quick movement to open the circuit. Asthe temperature of the iron decreases after breaking the circuit theiron cools and the curved end 18 tends to resume its original positionas shown in Fig. 3. When the temperature has fallen a suiicient amountto require additional heating the curved end 18 releases the plate 36 topermit the concavoconvex section of the plate 28 to return to itsoriginal position whichit does by a quick movement thus reengaging thecontact 32 with the plates 39 and 40 to again complete the circuitthrough the heating coil, when the operation may be repeated as long asthe iron is'in use and accidental overheating entirely avoided.

If it is found desirable to turn 0H the current from the iron withoutremoving the plug 6 and when the temperature is below the point Wherethe circuit is broken automatically, this may be accomplished bymanually operating the arm 56 to rotate the disk 53 from the positionshown in Fig. 3 to the position shown in Fig. 2 when the pin 65 willslide over the beveled tip of the curved end 18 of the hollow closedelongated member and thus force the curved end outwardly against theplate 36 and cause the contact 32 to assume the position shown in Fig. 2by a quick movement and thus break the circuit. In this way both manualand automatic means are provided for breaking the circuit, and after thecircuit has been broken by manual operation of the disk, the arm 56 maybe returned to its original position Aby the operator and the curved end18 of the tube released whereby the switch is permitted to close thecircuit provided that the temperature of the iron has fallen below thepoint at which the automatic means is eective to break the circuit.

While we have illustrated certain specific means for supporting andactuating the switch` and a certain form of thermostat for controllingthe operation of the same, these elements are capable of wide variationsin arrangement, and well known equivalents may be substituted for theparticular elements shown without @parting from the spirit and scope ofour invention, when broadly pended claims.

What we claim is:

1. In a control mechanism for an electrically heated device, thecombination of a hollow tubular member having a portion thereof irmlyheld against movement and an end portion free to move in response tovariations in temperature, resilient means Y tending to return themovable portion of said member to its initial position after movementdue to increase in temperature, a switch member provided with adistortable portion and having a movable contact portion, and means forexerting pressure upon the distortable portion of said switch memberupon movement of the free portion of said tubular member to eiiect quickmovement of said contact portion and break an electric circuit. y

2. In a control mechanism for an electrically heated device, thecombination of a heat responsive member having a resilient portion Afreeto move in response tov variations in temperature, a snap switch havinga distortable portion actuatable upon movement of the free portion ofsaid heat responsive memberto break an electric circuit, resilient meansfor returning the freely movable portion tof the heat responsive memberto its normal position, and manually operable means for moving the freeportion of said heat responsive member and said snap switch intoposition tobreak the electric circuit.

3. In a control mechanism for an electrically heated device, thecombination with an elongated heat responsive member having one endportion thereof held against movement and the opposite end portion freeto move in response to variations in temperature, of a snap switchhavingv one end portion thereof fixed and the remaining portion of saidswitch free to move and provided with a sensitive area locatedintermediate its ends and adapted upon the application of pressurethereto to eii'ect quick movement of the free end portion o f saidswitch member in a direction opposite to the direction of the appliedpressure, and means for applying pressure to the sensitive area of saidswitch member upon movement of the free end portion of said heatresponsive member in response to an increase in temperature. Intestimony whereof we have axed our slgnatures.

PETER DE LANGIE. GODFREY A. DE LANGIE.

construed in connection with the ap-

